Composition roofing material



May 13, 1941. L. Kmscl-:BRAUN TAL COMPOSITION ROOFING MATERIAL Filed Nov. 9, 1939 um.. Q

O Ov. U0. A o sNO composition roofing material and lmaterial does slowly moisture. This absorption sometimes takes place Patented May 13, 1941 2,241,819 COMPOSITION ROOFDTG MATERIAL Lester Kirschbraun, New York, N. Y., and Richard H. Cubberlcy,. Rutherford, N.-

J., assignors to The Patent and Licensing Corporation, New

York, N. Y., a corporation of Massachusetts Application November 9, 1939, Serial No. 303,524

(Cl. l08-7) 16 Claims.

This invention pertains to improvements in more particularly to improvements in composition roong of the type made from a base of rag or other fibrous felt saturated with asphalt and provided on its weather surface with a weather protective coating of asphalt, in which mineral or other surfacing material is partially embedded as a masking, wearing or decorative medium.

Composition material of this general character has long been employed for roofing, siding and similar purposes. In this type of material the felt base, generally composed of rag or other cellulosic bers, is impregnated with asphalt or other water-resistant saturant which coats the individual bers and substantially nils the void spaces between the fibers. The chief function of the saturant therefore is to impart water resistance to the fibers and thereby to prevent their decay. The layer of coating which is applied to the saturated felt base, usually in thicknesses of from 0.030 to 0.050 of an inch and usually comprising an asphalt of somewhat higher consistency and higher melting point than the asphalt used as the saturant, serves essentially'as the weather protective covering for the saturated felt base and also as a medium for afllxing the layer of mineral or other surfacing.

Frequently, however, material of type, especially under make the same favorable, suffer from what is known as blistering. This blistering manifests itself in the form of small crater-like eruptions on the surface of the material. These blisters not only detract from the appearance of the product but since the eruptions extend almost always through the entire depth of the weather protective coating layer, they thus permit ready access of rain, moisture, etc. to the felted fibrous base and thus hasten the destruction of the material.

'I'his blistering occurs chiefly and is particularly aggravated in those climates or at those seasons of the year in which high heat and humidithis general ty prevail. Blistering is due in large measure,

to the slow .absorption of small quantities of moisture by the saturated felt. Although efforts have been made. as by increasing the degree of saturation of the felt. to eliminate the tendency for the felt base to absorb moisture. the fact is that notwithstanding the improved modes of saturation that have been employed in more recertain conditions which 5 cent years. the saturated felt base in this type of absorb small quantities of through the weather surface of the roong, from the atmosphere or from rain. Moisture is also absorbed by the saturated felt base through the exposed cut edges of shingles. Moisture is most readily absorbed through theunderside of the material after it is applied, this underside being generally, according to commercial requirements and usage, only thinly coated. The underside of the material is frequently moist from condensation or from thev capillary creepage of water between adjacent overlying courses of shingles, and this moisture becomes absorbed quite readily because of the thin coating applied to the underside.

The moisture is accumulated slowly by the saturated felt and if the felt has thus absorbed or otherwise taken up -a suiilclent amount of moisture, even ifthe amount is as little as 1%' by weight of the product, and the felt then is's'ub jected to elevated temperatures such as those of solar heat, the water vapor `nds escape through the overlying layer on the upper or exposed surface and forces the latter into bubbles. These bubbles finally, upon rising to the surface of therooflng, become ruptured and form a blister. The number and size of these blisters depends upon theamount' of moisture absorbed by the felt which nds its escape in the manner de scri It is not unusual, where the conditions contributing to the blisters are sufllciently aggravated, to find these blisters in sizes varying from that of a pin-head toas large as one-quarter of an inch in numbers sufficiently frequently to mar the normal appearance of the surface as well as to shorten the life of the material. The eruption of Vthe bubble upon `reaching the surface frequently carries sufficient asphalt with it to form a rim around the has been provided with a layer of mineral such as crushed slate, the particles of the latter are forced away or otherwise displaced by the eruption of the bubble which forms the blister. In general, it may be stated that the ei'fect of this blistering on the life ofthe product is very serious, often reducing its effective life by as much as one-half or even two-thirds of its normal expectancy.-

The invention has for its primary purpose the prevention of blistering in composition shingles made' from material of the general character described.

We are aware of various means heretofore proposed i'or reinforcing the asphaltic coating employed for the weather-protective layer of th`ese of asphalt coating in diameter; and v blister, and where the surface' products, such as the use of higher melting point asphalts and the incorporation of asbestos fiber or like materials in the coating, but these expedients do not give satisfactory results so far as concerns the elimination of the effects of blistering. The failure of these expedients to give satisfactory results is explainable by the fact that asphalt thus treated remains substantially thermoplastic and hence does not substantially minimize to a suflicient extent the bubble formation which gives rise to the production of the blisters.

In accordance with our invention, the blistering propensity of composition shingles may be eliminated by applying to at least that part of the Weather coating of asphalt or the like on the portion of the shingle which will be exposed to the weather, a layer of thin, impervious material such as metal foil or similar membraneous sheet material which is suciently strong to reinforce the Weather coating and enable it to resist the force of vapor generated at elevated temperatures from moisture absorbed by the felt base. In this manner, water vapor seeking its escape from the felt base will find its path of least resistance through the back surface of the materia! rather than through the upper or exposed surface thereof.

In carrying out the invention, the layer of metal foil or other membraneous material is interposed between a first layer of coating asphalt extending over the entire upper surface of the shingle and a second coating of asphalt applied over at least the portion of the upper face of the shingle which is exposed to the weather in use. The invention accordingly finds its principal utility in connection with those forms of shingles which are made with an overlay layer of asphalt coating and mineral surfacing applied to the upper face of the shingle along the butt or exposed portion thereof, or extending over the entire upper face of the shingle.

In the accompanying drawing- Fig, 1 is a plan view of the upper face of a shingle in the form of a so-called square butt strip, embodying the invention,

Fig. 2. is an enlarged cross-section of the shingle taken transversely along the line 2 2 of Fig. 1,

Fig. 3 is a diagrammatic view showing instrumentalities that may be employed in the manufacture of the shingle of Fig. 1,

Fig. 4 is a View in plan taken along the line 4 4 of Fig. 3, and

Fig. 5 is a plan view of a part of a parent sheet prepared in accordance with the invention and from which shingles of the form of Fig. 1 may be produced.

Referring first to Figs. l and 2, an embodiment of the invention is there illustrated in connection with the well known form of square butt strip shingles. It will be evident, however, from the description set forth herein that the invention may be embodied in shingles and shingle strips of forms other than the square butt strip which has been selected herein for the purpose of illustrating and describing the invention.

The shingle illustrated comprises a horizontally elongated strip indicated generally by the numeral I0, having a body portion II and a butt portion I2. The butt portion may be subdivided into tabs I3 by transverse slots I4, the ends of the strip being provided with right angular notches l5. The upper ends IS and l1 of the slots I4 and notches I5,'respectively,v may terminate at or slightly below the upper boundary of the butt or portion of the strip to be exposed to the weather in use, this butt or exposed portion being of a transverse dimension somewhat less than that of the body portion to provide the required headlap.

These shingles are made from a base consisting of a felted sheet made from a fibrous stock including rag fibers, news and other cellulosic ber, such as wood ber. The felt base, indicated by the numeral 20. is saturated with asphalt of say 140 to 160 F. melting point, or other water-resistant saturant. the saturating step being conducted in any Well-known manner to obtain the maximum possible degree of saturation, which desirably amounts to about to 98% of the capacity of the sheet to absorb the saturant. The upper face of the shingle is provided with a Weather protective coating of asphalt 22 applied directly to the saturated felt base 2U. The coating layer 22 may consist of high melting point (212 to 220 F.) blown asphalt as usually employed for this purpose. In accordance with the invention, there is aixed to the coating layer 22 a thin sheet 23 of a material which is impermeable to moisture Vapor and gases. For this purpose there may be employed metal foil such as aluminum foil. The sheet 23 preferably extends from the butt edge I8 of the shingle upwardly to a distance about one-half to one inch beyond the butt or exposed portion of the shingle, i. e. beyond the upper edges of the slots I4 and notches I5. The remaining area of the asphalt coating layer 22 between the inner edge of the sheet 23 and the upper edge 24 of the shingle is provided with a surfacing layer 25 of granular material partially embedded in the coating layer 22. comminuted slate or other mineral granules or may consist of granules of cork, ground coke or the like. Instead of using such granular material for surfacing the areas of coating layer 22 extending beyond the sheet 23, the latter may, if desired, be extended to cover the whole of the coatinglayer 22. Applied over the sheet 23 is a second or overlay layer 21 of a weather protective coating which may consistof high melting point blown asphalt. In the embodiment shown, this coating layer 21 extends from the butt edge I8 of the shingle to slightly beyond the inner boundary of the sheet 23, as indicated at 28. Where the sheet 23 is coextensive with coating layer 22, the overlay coating may terminate a short distance, say one inch, above the upper ends of -slots I4 and notches I5. The overlay coating layer 2'I is surfaced with a layer 30 of mineral surfacing such as crushed slate, artiiicially colored slate granules, articially colored trap rock granules or the like, partially embedded in the coating layer 21.

The bottom face of the shingle may also be provided with a layer 3| of asphalt coating. This back coating, in accordance with customary practice, is comparatively thin and it may be surfaced with non-adhesive material such as powdered talc or mica.

Those skilled in the art will recognize from the foregoing description of the shingle shown in Figs. 1 and 2 that it comprises essentially a so-called thick butt shingle which is presently in commercial use. It differs therefrom, however, primarily by the provision of the sheet 23 of material impermeable to moisture vapor and gases, afIixed to the coating layer 22. In the customary form of these thick butt shingles, the

'Ihis surfacing may consist of Y arrangement shown, the sheet is of a width four times the width of the shingle I0. In the coating device 45 the saturated felt sheet is provided with an asphaltic coating layer on its upper surface (to constitute the coating layer 22 of the finished shingle) as by means of a supply spout 46. This coating layer may consist of blown asoften expelling the granules of layer in their path.

By means of the sheet 23 of the impermeable material, such as metal foil, employed in accordance with the invention, this tendency of vaporized moisture to escape through the upper surface of the shingle is counteracted to an extent sufficient to cause the vapor to find its escape through the back or undersurface of the shingle, where the occurrence of blisters is neither evident nor as harmful as when these blisters occur on the upper surface, particularly in the portion thereof which is exposed to the weather in the laid arrangement of the shingles. In order to accomplish this Objective, the sheet 23 may consist either of plain metal foil or that form of metal foil which carries a backing of thin vtissue-like paper or it may consist of sheets made of regenerated cellulose such as cellulose acetate,

cellulose nitrate, etc. In any event,` however, the sheet 23 must be impervious to moisture vapor and gases, must be strong enough to resist rupture by the force of expanding vapor bubbles that may pass through the coating layer 22, and yet suciently thin and light in weight so as not to add materially to the normal weight of the finished product. By using a sheet of this character it becomes possible to produce shingles of the character described which will be substantially free of the tendency to form blisters on the exposed surface, without adding materially to the weight or cost of the finished product. Inl making blister-proof shingles according to the invention, we have successfully employed aluminum foil calipering 0.00025". It should be evident, however, that copper or other metal foils may be used in lieu of the aluminum foil and that as already indicated, other thin, membraneous material such as sheets of regenerated cellulose having the above stated characteristics may be employed as the layer 23.

Although in the embodiment of the invention above described, the overlay coating of asphalt 21 extends from the butt edge of the shingle upwardly to a distance slightly beyond the upper ends of the cut-outs I4, I5, it should be evident that this overlay coating layer 21 may extend over the entire transverse dimension of the shingle, whether the sheet 23 terminates slightly above the cut-outs, or extends over the full area of coating layer 22. In either of such instances, the surfacing layer 30 may be correspondingly extended so as to cover'the full width of coating layer 21. l

In Figs. 3'and 4, there is illustrated more or less diagrammatically an'arrangement of apparatus for producing shingles such as shown in Figs. 1 and 2. Numeral 40 indicates a sheet of fibrous felt which has, by means of suitable saturating equipment (not shown), been impregnated with water-resistant asphalt. vThe saturatedsheet may be fed continuously from a looper 4| over guide rolls 42, 43 to a coating device indicated generally by the numeral 45. 'In the particular l coated face of the sheet.

phalt of say 210-220 F. melting point, mixed, if desired, with suitable amounts of mineral filler in accordance with customary practice. The coating layer deposited on the sheet from the spout 46 may be leveled to the desired thickness by means of a doctor roll 481 At the same time the bottom surface of the sheet is provided with a comparatively thin layer of similar asphaltic coating (to constitute the coating layer 3l of the finished shingles), this coating layer being applied as by means of a coating roller 50 revolving Immediately as the coated sheet passes beyond the coating device 45, spaced ribbons 53, 54 of aluminum foil or other membraneous material of the character described, may be fed asindicated at 52, from supply rolls onto the upper Each of these ribbons is of a width twice the width of the layer of metal foil 23 in the finished shingle, the supply rolls being arranged on a mandrel 55 in spaced relation from one another and from the adjacent longitudinal edges of the sheet so that the ribbons will each occupy those portions of the sheet from which .the butt portions of the strips are subsequently to be formed, as indicated in Fig. 5. At

about the same time that the ribbons of metal foil are united with the hot layer of coating asphalt on the upper face of the sheet, mineral or other suitable granules are showered onto this coating in the space between the ribbons and on opposite sides of the outer margins thereof. These granules may be deposited from a hopper 51 which may be subdivided into separate compartments, the central compartment 58 contain` ing the granules to be deposited between the two ribbons of foil and the end compartments 59, 60 containing the granules to be deposited on the coating beyond the outer margins of the ribbons 53, 54 respectively. The hopper 51, as indicated in the drawings, is mounted adjacent a reversing roll 62 and as the sheet passes around this roll, the granular material deposited from the hopper 51 is pressed into the surface of the coating layer and at the same time the ribbons 53, 54 are firmly affixed to the coating layer. On the opposite side of roll 62 there is located a supply box 64 containing powdered mica, Ialc or similarsurfacing material which is applied to the coating layer onthe under face of the sheet supplied by the coating roll 50. As the sheet passes beyond the reversing roll 62 surplus granules deposited on the sheet from hopper 51 are returned by gravity to the hopper. The sheet then passes around a press drum 65 and then over any suitable number of additional press drums 61 which may be either` heated or cooled, as desired.

.At any suitable point beyond the last of the series of press drums 61, there is mounted a supplyl box 69 containing high melting point blown asphalt mixed, if desired, with suitable quantities of mineral fillers. yThis supply box 691s provided in one of its end walls withopenings each accommodating one of a pair of spaced coating rolls 10,1I to feed asphalt from the supply box 69 and apply it to the sheet in the form of bands covering the ribbons 53,54 of metal foil and preferably extending widthwise to a distance slightly beyond the margins of the ribbons. Immediately beyond the coating device 69 there is mounted a hopper 12 containing mineral granules, this hopper being preferably divided into compartments '13, 'It from which mineral granules 'are showered onto the bands of the overlay coating applied by the rolls 10, 1i respectively. The sheet then passes around a reversing press drum 'H5 beyond which surplus granules may return by gravity to the hoppers '43, 1t, the sheet then being fed around a series of additional press drums it for firmly amxing the layer of mineral granules to the overlay coating, these additional press drums being cooled if desired in order to assist in the cooling of the sheet. It will be understood that the coating supplied by the coating device 6d is that which will constitute the coating layer 2T of the .finished shingle and that the surfacing of mineral granules supplied from the hopper 'i2 will constitute the surfacing layer Sil of the finished shingle.

Beyond the last of the series of press drums 16, the sheet may be gathered in a looping device ld and from this looper the sheet may be fed to any suitable cutting devices for forming shingles of the desired size and conguration. In making the particular style of shingle shown in Fig. 1, the cutting devices may be arranged to form a series of spaced transverse slots 80 and a series of similarly spaced transverse slots 8i through the band of overlay coating and mineral surfacing supplied from the coating roll Ill and compartment 13, the slots of these two series extending in opposite directions from the longitudinal center of the ribbon 53 applied to the sheet, for a distance slightly less than one-half the width of the overlay band of asphalt coating and mineral surfacing. Thus, the slots 80 will constitute the tab-defining slots I4 of the shingle strips cut from lane A. of the sheet while the slots 8l will constitute the tab-defining slots of the strips of lane B cut from the sheet. Similar series of transverse slots 83, 84 may be formed through the other band of overlay coating and mineral surfacing applied to the sheet, to constitute the tabdening slots of shingles cut from a third lane C and a fourth lane D respectively. The shingles are severed from the sheet by longitudinal slits 85, 86 extending midway of each of the overlay bands and intersecting the inner ends of the slots 80-8l and 83-84 respectively, the sheet also being slit longitudinally along the center line at 8T and transversely as indicated at 88 to form the end edges of the body portions ofthe strips.

While the invention has been described with reference to the so-called square butt strip shingles, it is believed that the description will suflice to indicate quite clearly to those skilled in the art that the invention may be embodied in other forms of shingles, including shingle strips of various other shapes as well as individual shingles.

We claim:

1. A shingle comprising a base of flexible fibrous felt saturated with asphalt or vthe like, said base carrying a layer of asphaltic coating on the upper face thereof, a unitary sheet of foillike membraneous material applied to said coating along that portion of the shingle which is to be exposed to the weather, a second layer o f asphaltic coating overlying said membraneous sheet, and a layer of mineral granules partially embedded in said second coating layer, said membraneous sheet being impermeable -to mois- -ture vapor emitted from the felt base during exposure of fthe shingle to the weather.

2. A shingle as dened in claim l, wherein said membraneous sheet consists of metal foil.

3. A shingle as defined in claim 1, wherein said membraneous sheet consists of aluminum foil.

4. A shingle as dened in claim 1, wherein said membraneous sheet consists of regenerated cellulose.

5. A shingle comprising aexible fibrous fel 4saturated with asphalt or the like, said base carrying a layer of asphaltic coating on the upper face thereof, a unitary sheet of foil-like membraneous material applied to said `coating along that portion of the shingle which is to be exposed to the weather and having its upper edge located slightly above the upper limit of said exposure, the remaining area of said coating layer from'said upper edge of the sheet to the upper edge of the shingle being surfaced with granular material, a second layer of asphaltic coating overlying said membraneousA sheet and a layer of mineral granules partially embedded in said second coating layer, said membraneous sheet being impermeable to moisture vapor emitted from the felt base during exposure of the shingle to the weather.

6. A shingle as defined in claim 5, wherein said membraneous sheet consists of metal foil.

'7. A shingle as defined in claim 5, wherein said membraneous sheet consists of aluminum foil.

8. A shingle as defined in claim 5, wherein said membraneous sheet consists of regenerated cellulose.

9. A shingle comprising a flexible fibrous felt saturated with asphalt or the like, said base carrying a layer of asphaltic coating on the upper face thereof, a unitary sheet of foil-like membraneous material applied to said coating along lthat portion of the shingle which is to be exposed to the weather and having an upper edge located slightly above the upper limit of said exposure, the remaining area of said coating layer from said upper edge of the sheet to the upper edge of the shingle being surfaced with granular material, a second layer of asphaltic coating overlying said membraneous sheet and lterminating substantially along said upper edge thereof, and a layer of mineral granules partially embedded in said second coating layer, said membraneous sheet being impermeable to mois- -ture vapor emitted from the felt base during ex posure of theshingle to the weather.

10. A shingle as defined in claim 9, wherein said membraneous sheet consists of metal foil.

11. A shingle as defined in claim 9, wherein said membraneous sheet consists of aluminum foil.

12. A shingle as defined in claim 9, wherein said membraneous sheet consists of regenerated cellulose.

13. A shingle comprising a flexible fibrous felt saturated with asphalt or the like, said base carrying a layer of asphaltic coating on the upper face thereof, a unitary sheet of foil-like membraneous material applied tosaid coating along that portion of the shingle which is tofbe exposed to the weather and having an upper I edge located slightly above the upper limit of said exposure, the remaining area of said coating layer from said upper edge of the sheet to the upper edge of the shingle being surfaced with granular material, a second layer of asphaltic coating overlying said membraneous sheet and said layer of granular surfacing on the first named coating, and alayer of mineral granules partially embedded in said second coating layer, said membraneous sheet being impermeable to moisture vapor emitted from the felt base during exposure of the shingle to the weather.

14. A shingle as deilned in claim 13, wherein said membraneous sheet consists of metal foil.

15. A shingle as defined in claim 13, wherein said membraneous sheet consists of aluminum foil. l

16. A shingle as dened in claim 13, wherein said membraneous sheet consists of regenerated cellulose.

. LESTER KIRSCHBRAUN.

RICHARD H. CUBBERLEY. 

